In a sputtering apparatus, if a thin film is formed on the inner wall of the process chamber, maintenance of the apparatus becomes difficult. Hence, an interchangeable protection shield is placed in the process chamber to protect the inner wall. The distance between a target and a substrate (to be referred to as a TS distance hereinafter) is known to affect the evenness of the thickness or quality of a formed film. In addition, the film thickness or film thickness distribution tends to gradually degrade as the target is gradually sputtered, and erosion progresses, as is known. Concerning these phenomena, changing the TS distance is a very effective way to improve or stabilize film quality.
The shield provided in the sputtering apparatus is formed from a plurality of divided shields to enable the change of the TS distance. Gaps are formed between the shield parts. To prevent a film from reaching the inner wall of the process chamber via the gaps, the gaps have a narrow path (labyrinth) structure (for example, PTL 1).